Mercedes' British driver Lewis Hamilton leads Red Bull's Dutch driver Max Verstappen during the afternoon session of the first day of the Formula One pre-season testing at the Bahrain International Circuit in the city of Sakhir on March 12, 2021. (MAZEN MAHDI / AFP)

LONDON - Lewis Hamilton can win a record eighth Formula One world championship while his Mercedes team celebrate an unprecedented eighth successive title double in the longest ever season, pandemic permitting.

Four-times champion Sebastian Vettel has moved from Ferrari to Aston Martin

Alternatively, the planned 23-race championship could mark the end of an era with Red Bull’s Max Verstappen leading a generational changing of the guard.

It may even be ‘farewell Sir Lewis’, with the newly-knighted Briton - set also to become the first driver to win 100 races - extending his contract only to the end of 2021.

“I chose to have a one-year deal so that I could see how the year goes,” he said.

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The season also sees a Schumacher lining up on the starting grid for the first time since Michael’s departure at the end of 2012 and Saudi Arabia making its debut with a night race in Jeddah.

Red Bull’s car was quick, stable and reliable in pre-season testing, with Verstappen fastest, while Hamilton and team mate Valtteri Bottas were unsettled by the skittish handling of the Mercedes.

Mercedes say Honda-powered Red Bull have the edge on performance but Red Bull, who have brought in the experienced Mexican Sergio Perez alongside Verstappen, say Mercedes are very much the favourites.

Either way, the stage is set for the closest-fought battle yet between the king and the youngster who would seize his throne.

The March 28 season-opening race in Bahrain will provide some clarity, with testing notoriously unreliable as an indicator of form, but the title battle looks set to remain between last year’s top two teams.

“They’ve had some really good running, both drivers have been looking quite strong. They are going to be a different machine or animal this year with a really good, strong line-up and a really good car,” said Hamilton of Red Bull.

“You can imagine they are going to be right there in the first race and it’s going to be a great long battle with them through the year.”

The grid will feature four world champions, with the return of two-time titleholder Fernando Alonso, now 39, to the team that used to be Renault and will now be racing under Alpine branding and with new leadership.

Four-times champion Sebastian Vettel has moved from Ferrari to Aston Martin, competing as a constructor for the first time since 1960 after Racing Point changed their name, and 41-year-old Kimi Raikkonen races on at Alfa Romeo.

McLaren are the only team to have changed engine supplier, switching from Renault to Mercedes, and they also have Australian Daniel Ricciardo replacing Carlos Sainz, who has joined Ferrari.

The Italian team endured their worst season in 40 years in 2020, failing to win a race and finishing sixth overall, but a more powerful engine should help them fight more for podiums at least.

Three rookies make their debuts, with Mick Schumacher attracting much of the attention as the Formula Two champion follows the path of his Ferrari great father.

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The German is joined at Haas by Russian Nikita Mazepin, whose billionaire father has provided the team’s title sponsorship,

Japan will also have a driver on the grid for the first time since 2014, with Yuki Tsunoda joining AlphaTauri.

Crowds could return, at least for the later grands prix, after most of 2020 was spent racing behind closed doors due to the pandemic, and experimental Saturday ‘sprint qualifying’ races are set to feature with points awarded.

The shape of the season could still change, however, with uncertainty over whether all of the 23 races will happen. Australia, the usual opener, has already moved to November.